CS 4119: Computer Networks

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CS 4119 Computer Networks

• Henning Schulzrinne
• Dept. of Computer Science
• Columbia University
• http//www.cs.columbia.edu/hgs

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Why learn about computer networks?

• Almost all modern software applications are
  distributed
• from enterprise applications to video games
• General useful principles
• dealing with asynchronicity
• unreliable components ? predictable end systems
• (network) life is random and unpredictable
• work with other implementations that you have
  never met before

• Theory
• congestion control
• routing
• How does the world really work?
• email, the web, P2P applications, DSL,
• Learning to create professional-grade network
  applications
• not just use libraries as black boxes

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CS4119 as Foundation

• Lots of Columbia Computer Science classes build
  on this
• COMS 4180 Network Security
• COMS 6181 Advanced Internet Services
• COMS 6998 Advanced Internet Routing
• COMS 6180 Modeling Performance Evaluation
• COMS 6125 Web-enhanced Information Management
• ELEN 6950 6951 Wireless Mobile Networks
• projects in a variety of research groups

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Course Information

• Introductory (first) course in computer
  networking
• Who is this course for?
• Undergraduates (senior), MS students, first-year
  PhD students
• Prerequisites
• Algorithms, operating systems, programming skills
  in C
• Course materials
• text Computer Networking A Top Down Approach
  Featuring the Internet, Jim Kurose Keith Ross,
  Addison Wesley, 5th edition, 2010
• web readings
• Class notes

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Course Information (more)
written homework assignments 4 20
programming assignments 3 20
lab assignments 1-2 10
midterm 1 20
final exam 1 30
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A bit about myself

• UMass Amherst, Bell Labs, GMD Fokus (now
  Fraunhofer), Columbia, FCC
• Research interest in networking (IRT research
  group at Columbia)
• performance and reliability
• multimedia systems
• security
• Active in Internet protocol standardization
• IETF

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Part 1 Introduction

• What is the Internet?
• What is a protocol?
• The network edge, core, and access networks
• Physical media
• Delay and loss in packet-switched networks
• Protocol layers, service models
• Internet backbones, NAPs and ISPs
• Standardization
• A brief history of computer networking Internet

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Part 2 Application Layer

• Principles of application-layer protocols
• The World Wide Web HTTP
• File transfer FTP
• Electronic mail in the Internet
• The Internet's directory service DNS
• Socket programming

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Part 3 Transport Layer

• Transport-layer services and principles
• Multiplexing and demultiplexing applications
• Connectionless transport UDP
• Principles of reliable of data transfer
• TCP case study
• Principles of congestion control
• TCP congestion control

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Part 4 Network Layer

• Introduction and network service model
• Routing principles
• Hierarchical routing
• IP the Internet Protocol (IPv4 IPv6)
• Routing in the Internet
• What is inside a router?

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Part 5 Link Layer LANs

• Introduction, services
• Error detection and correction
• Multiple access protocols and LANs
• LAN addresses and ARP
• Ethernet
• Hubs, Bridges and Switches
• Wireless LANs IEEE 802.11
• Network virtualization MPLS

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Time permitting

• Security
• see Network Security
• Multicast
• Overlay and peer-to-peer networks
• Multimedia
• see Advanced Internet Services